Zelko Igor N, Hussain Ahtesham, Malovichko Marina V, Wickramasinghe Nalinie S, Srivastava Sanjay
Superfund Research Center, University of Louisville, Louisville, KY 40202, United States.
Envirome Institute, University of Louisville, Louisville, KY 40202, United States.
Toxicol Sci. 2025 Jul 1;206(1):111-122. doi: 10.1093/toxsci/kfaf055.
Benzene is a ubiquitous environmental pollutant, abundant in both the outdoor and indoor air. Chronic exposure is associated with increased risk for cardiovascular disease; however, the underlying mechanisms remain unknown. We examined the effect of bioactive benzene metabolites on endothelial integrity. In vitro, highly reactive benzene metabolites, specifically trans, trans-muconaldehyde (MA, 10 µM), decreased the impedance of murine cardiac microvascular endothelial cells (MCMVEC) in a time- and dose-dependent manner and increased the endothelial permeability to 70 kDa dextran. Intradermal injection of MA (400 pmol) increased the vascular leakage by 54% (P < 0.0001) in adult male C57BL/6J mice. This was accompanied by increased levels of endothelial microparticles in the circulation. RNA sequencing of MA-treated MCMVEC and human aortic endothelial cells revealed the robust induction of heat shock proteins (HSPs), particularly members of the HSP70 and HSP90 families. Reactome pathway enrichment analyses suggested that MA dysregulates pathways associated with G protein-coupled receptor and heat shock factor-1-dependent transactivation. Pharmacological inhibition of HSP70s and HSP90s prevented an MA-induced increase in MCMVEC monolayer permeability. Similarly, pharmacological inhibition of Rho-associated coiled-coil-containing protein kinase (ROCK) attenuated MA-induced endothelial permeability in MCMVEC, accompanied by a dose-dependent activation of Rac1 GTPase. To assess the contribution of HSPs to MA-induced endothelial function impairment, we generated a transgenic mouse overexpressing HSPA1B (a member of the HSP70 family; HSPA1B-TGEC). MA exposure increased the vascular leakage by 15% (P < 0.05) in HSPA1B-TGEC mice as compared with the littermate controls. Collectively, our data suggest that MA increases vascular permeability by activating HSP and GTPase signaling pathways.
苯是一种普遍存在的环境污染物,在室外和室内空气中都大量存在。长期接触与心血管疾病风险增加有关;然而,其潜在机制仍不清楚。我们研究了生物活性苯代谢物对内皮完整性的影响。在体外,高反应性苯代谢物,特别是反式,反式-粘康醛(MA,10µM),以时间和剂量依赖的方式降低了小鼠心脏微血管内皮细胞(MCMVEC)的阻抗,并增加了内皮对70kDa葡聚糖的通透性。在成年雄性C57BL/6J小鼠中,皮内注射MA(400pmol)使血管渗漏增加了54%(P<0.0001)。这伴随着循环中内皮微粒水平的增加。对MA处理的MCMVEC和人主动脉内皮细胞进行RNA测序,发现热休克蛋白(HSPs),特别是HSP70和HSP90家族成员的强烈诱导。Reactome通路富集分析表明,MA使与G蛋白偶联受体和热休克因子-1依赖性反式激活相关的通路失调。对HSP70和HSP90的药理学抑制阻止了MA诱导的MCMVEC单层通透性增加。同样,对含Rho相关卷曲螺旋蛋白激酶(ROCK)的药理学抑制减弱了MA诱导的MCMVEC内皮通透性,同时伴有Rac1 GTPase的剂量依赖性激活。为了评估HSPs对MA诱导的内皮功能损害的作用,我们构建了过表达HSPA1B(HSP70家族成员;HSPA1B-TGEC)的转基因小鼠。与同窝对照相比,MA暴露使HSPA1B-TGEC小鼠的血管渗漏增加了15%(P<0.05)。总体而言,我们的数据表明,MA通过激活HSP和GTPase信号通路增加血管通透性。